Antifreeze appliance



May 3l, 1949. L w, BRECK 2,471,718

v ANTIFREEZE APPLIANGE Filed 06t- 11, 1948 W Y J ,m ml @nl E Nl wml; l?

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INVENToR. LAwmvcs W. Baux TTOENE Y Patented May 31, 1949 UNITED STATES PATENT OFFICE ANTIFREEZE APPLIANCE Lawrence W. Breek, Cleveland, Ohio Application October 11, 1948, Serial No. 53,917

Claims. (Cl. 62-1) This invention relates in general to freezing units for refrigerators and more particularly to a removable anti-freeze appliance for preventing the removable trays from becoming frozen and adhering to the freezing unit compartment.

It is common knowledge and experience that, while the freezing unit is performing its useful functionk of freezing the contents of the trays, it also collects moisture and freezes it into an ice formation, both on the tray and its compartment, rendering it difficult, if not impossible, to remove the trays without defrosting, applying hot water or the ill-advised resort to tools, which often result-s in damage to the tray and the unit itself.

In order to prevent this undesired ice forma,- tion, I propose to provide and employ a simple, inexpensive, easily insertable and removable appliance that will be highly effective for such purposes.

There are known substances which have a much lower freezing point than that of water and when mixed with water result in a solution having a much lower freezing point than that of water. The application and presenceof such a substance on the compartment and trays would have the beneficial result of lowering the freezing point of the collected moisture without interfering with the desired freezing of the contents of the tray.

There are other considerations, however, that mustrbe had, one being that some metals employed in they compartment and trays are subject to corrosion when exposed to certain substances having such low freezing points. Ac-

cordingly, the anti-freeze solution must be such that will lower the freezing point and, at the same time, not cause corrosion, either of the compartment or trays.

Another important consideration is the vehicle, or appliance, for maintaining a solution, having the required properties of anti-freeze and non-corrosion producing, in the proper zone for the prevention of freezing, sticking and trapping of the trays in the freezing compartment.

Accordingly, it is a primary object of my invention to provide such an appliance that will` include as a vehicle an absorbent material that is preferably immersed in a solution of antifreeze and non-corrosion producing properties with respect to the metal of the compartment and tray.

It is also an important object of my invention to carefully and accurately predetermine freezing temperature ranges required by the refrigeration unlt, the metal used in the compartment and trays, the anti-freeze strength required to prevent freezing, sticking and trapping of the trays and the required neutrality of the solution and the sheet itself, after immer-sion in the solution, with respect to acidity or alkalinity to prevent corrosion of the compartment or its trays.

A more specic object is to provide such an appliance that will not only prevent adhesive ice formation on the bottom, and possibly the sides, of trays, but also prevent such adhesive ice formation on the compartment in front of the trays, which latter may themselves be free to slide, but which are trapped by such ice formation against manual removal from the compartment.

With the foregoing and other objects in View, the invention resides in the combination of parts and in the details of construction hereinafter set forth in the following specification and appended claims, certain embodiment-s thereof being illustrated in the accompanying drawings, in which:

Figure 1 is a view in perspective of an vopen refrigerator freezing compartment showing one vacant chamber with the tray and anti-freeze appliance removed from the supporting shelf, and also showing other chambers of the compartment with trays resting on my anti-freeze appliances disposed between the trays and the supporting shelves;

Figure 2 is a schematic view showing my appliance being immersed by hand in a solution of predetermined anti-freeze and other properties; and

Figure 3 is a view in perspective, showing modified form of my anti-freeze appliance folded downwardly at its front end and also upwardly at its sides.

Referring more particularly to the drawings, there is illustrated a conventional refrigerator freezing compartment I with a relatively small tray 2 and a relatively large tray 3 in the respective chambers of the freezing compartment. One chamber 4 of the freezing compartment is shown with its tray removed, to show the upper surface and front edge Il of the shelf of the chamber of the compartment. In the other chambers my anti-freeze appliance 5 is shown to be interposed between the shelf of each chamber and the bottom of each tray 2 and 3.

As an added and important feature, I have shown the appliance 5 to consist of a length greater than the depth of each chamber so that it may be bent downwardly over the front edge Ii of the shelf of each chamber. Specifically, each sheet may include a dotted line 6, or other indicia, to denote to the operator the line upon which the sheet should be folded to obtain a downwardly depending lip 1. The purpose of this lip 1 is to subject the front edges of the comipartment chambers with the anti-freeze properties inherent in the anti-freeze sheet so as to prevent adhesive ice formation that would hold the tray captive, even thou'gh the latter itself were not stuck by freezing to the interior of the compartment.

As shown in Figure 3. in addition to the front lip 7, the sheet may be made to exceed, when flat, the width of the chamber and be bent up- Wardly along lines 9 to provide side walls I0.

Figure 2 is merely a schematic showing of a container 8 containing some of my prepared antifreeze solution, into which a sheet is being immersed, which means of impregnation of the solution of non-corrosive and anti-freeze properties into the sheet appliance is preferable, due to considerations explained more fully hereinafter. The sheet should preferably be of such material as to hold the ingredients of the solution in suspension. It is preferably absorbent and may thus be brous, or it may be of spongy material.

As explained by the treatise by Wilfred W. Scott, Standard Methods of Chemical Analysis, 5th edition, vol. 2, March, 1939, at pages 2274, et seq., acidity and alkalinity of solutions are capable of denite measurement, regardless of their otherwise measured strength and are expressed by the symbol pH which is a symbol logarithm of l/H hydrogen ion concentration. The hydrogen electrode is recognized as a fundamental standard in determinations of hydrogen ion. The pH scale is used to denote intensity of acidity and alkalinity. The numbers from 0 to 14 are used to express pH values, that is, intensity of acidity and alkalinity. The value pH 7.0, halfway between 0 and 14, is the neutral point, that is, a solution having a pH of 7.0 is neither acid or alkaline. The numbers below 7.0 denote acidity, the intensity of acidity increasing as the numbers decrease toward 0. Numbers '7.0 to 14.0 are used to denote alkalinity, the intensity of alkalinity increasing as the numbers increase toward 14.0. The theory of ionization holds that certain types of chemical compounds are split apart or disassociated in an aqueous solution, yielding electrically charged ions, which are responsible for many properties of solutions, including their acidity and alkalinity.

As stated before, I want my anti-free appliance to comprise a suitable vehicle for carrying the predetermined properties of a prepared solution so that the appliance will be eiective as an antifreeze agent and, at the same time, not be the means of inducing corrosion of the metal compartment or trays.

By way of example, only, and merely for purposes of illustration, I may elect to use sodium chloride (NaCl), or common salt, as an antifreeze agent because of its lowering of the freezing point in solution. If aluminum is employed as the metal for the freezing compartment and trays, the presence of a highly acid or alkaline salt solution would cause corrosion of the aluminum. Therefore, in taking advantage of the anti-freeze properties of salt in water solution I add to such solution an alkaline substance such as sodium carbonate (NazCOz), or an acid such as hydrochloric acid (HC1), to reduce or increase pH value of the resulting solution to a number in the vicinity of 7.0. As to the vehicle, itself, l. may nd it preferable to use relatively thin sheets of inexpensive common bloti'ng paper. These sheets are preferably immersed in the prepared solution so as to take advantage of the absorbent properties of the paper. enabling the sheet to hold in suspension and retain the chenilcals throughout the thickness of the sheet.

Factors to be considered other than the pI-I value of the solution itself are the pH value of the sheet before immersion. the temperature range of operation of the freezing compartment and the anti-freeze strength necessary in solution in water.

For instance, for a given instance my process may call upon me to prepare a 10% solution of salt in water. I then accurately determine, by a pH scale, the pH of the solution and adjust the pH of the solution, by adding a weak acid or alkaline, as the case may be, to approximately a pH of 7.0. I then preferably immerse the sheet of blotting paper, of preferably controlled pH of '1.0, into the prepared solution. I then remove the sheet from the solution to dry and later check a. small sample of the sheet for its pH value, which should preferably be between '7.0 and '7.2. It is to be understood that excessive alkalinity. as well as excessive acidity, may induce metallic corrosion.

In the event that the pH value of the immersed, impregnated and dried sheet is either above 1.2 or below 7.0, compensation should be made. For pH values great-er than 7.2 the pH of the solution should be adjusted to a lower value and a test sheet tested for its pH. For pH values of less than '7.0 the pH of the solution should be adjusted to a higher value and a test sheet tested for its pH.

The strips of paper thus impregnated in the solution under careful pH control and subsequently dried may then be cut into strips of any desired dimensions and packed for sale and distribution and subsequent use for their above described intended purpose.

I claim:

1. An appliance for preventing an ice cube tray from freezing to a refrigerated supporting surface; said appliance comprising a fibrous absorbent sheet having embedded in its interstices particles of sodium chloride and particles of a second solid having the property of controlling the resultant of the pH values of the sodium chloride and of the fibrous sheet and giving a neutral pH value to moisture condensing on the tray and support.

2. An appliance for preventing an ice cube tray from freezing to a refrigerated supporting surface, said appliance comprising a brous absorbent sheet having embedded in its interstices particles of acid sodium chloride and particles of a second solid sodium carbonate having the property of controlling the resultant of the pH values of the sodium chloride and of the brous sheet and giving a neutral pH value to moisture condensing on the tray and support.

3. An appliance for preventing an ice cube tray from freezing to a refrigerated supporting surface, said appliance comprising a fibrous absorbent sheet having embedded in its interstices particles of acid sodium chloride and particles of a second solid alkaline carbonate having the property of controlling the resultant of the pH values of the sodium chloride and of the fibrous sheet and giving a neutral pH value to moisture condensing on the tray and support.

4. An appliance for preventing an ice cube tray from freezing to a refrigerated supporting surface, said appliance comprising a fibrous absorbent sheet having embedded in its interstices particles of sodium chloride and particles of a second solid having the property of controlling the resultant of the pH Values of the sodium chloride and of the fibrous sheet and giving a pH value of 7.0 to 7.2 to moisture condensing on said tray or support.

5. In combination in a freezing unit having trays for containing material to be frozen and shelves for supporting said trays, an anti-freeze appliance adapted to be removably placed be- ,tween said shelves and trays to prevent the tray from freezing to the shelf, said appliance comprising a fibrous absorbent sheet of material having embedded in its interstices particles of sodium chloride and particles of a second solid having the property of controlling the resultant pH values of said sodium chloride and the fibrous sheet and giving a neutral pH value to moisture condensing on the tray and shelf, said appliance having its side edges extending upwardly adjacent the side walls of said trays and its forward end extending forwardly and downwardly over the front edge of said shelf.

LAWRENCE W. BRECK.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,679,292 Carrey July 31, 1928 1,751,899 Whitfield Mar. 25, 1930 1.991,702 Safford Feb, 191935 2.178,387 Becker Oct. 31, 1939 2,429,521 Marquis Oct. 21, 1947 

